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Two-dimensional bar code, also known as a brief history of the development of two-dimensional bar code technology, first appeared in the 1940s, but its practical application and development was around the 1970s. At present, bar code technology has been widely used in GJ and all over the world, and it is rapidly spreading to all parts of the world. The application fields are more and more extensive and gradually penetrate into many technical fields. This pattern is very similar to a miniature archery target, which is called bull's-eye code.
The concentric circles of the target are drawn into rings by circles and spaces. In principle, the bull's-eye code is very similar to the later bar code, but unfortunately, the technology and commodity economy at that time could not print this code. However, 20 years later, Joe Woodland became the founder of UPC code as an engineer of IBM.